to drill or not to drill that is the question

project5k

Reef enthusiast
so i have my 75gal tank, its set up, and running, and has been since march, but i'm working on a new stand, and will want to move the tank to the new stand in the next couple weeks when i get it done.

my question is this, i'm using a HOB overflow right now, and that thing just worries me, after i got it all up and running its been fine, but it still scares me, so.... what i'm thinking is that when i move the tank, i gotta empty it, should i drill the back glass for overflows and returns, or should i just put it on the new stand and keep using what i have now?

one of the things that i'm fighting with is that when i go to the new stand, i'm also going to build a new canopy, and all that junk hanging over the back wall of the tank is gonna be in the way of the canopy, the way i wanted to build it....

i got this tank used and set up from a friend, he got it used and set up from someone else, so we dont know who the manuf. is. I've looked at the back glass with my ploarized sunglasses, but i didnt see anything, but then again the lighting on the back of the tank is basically non existant... so is it worth the risk? or do i stay with what i have now? i cant afford to just run out and get another tank if i kill this one, so i guess if i break it, then i'll just have to sell all my fish, cause i really dont have anywhere to put them... i'm thinking about using a small 20 gal to put them in while the move is happening, but thats just a temp thing, that would only really be set up to hold them for a couple hours at most..

this whole decision makes me more nervous than buying the thing in the first place
oh, and the other question, can i drill the back glass with it verticle, or do i have to lay the tank over so that the back is parallel to the ground to drill it? i know about the water and putty thing, but i was wondering if it could be done upright?

so.... to drill or not to drill? and if i drill, what size bulkheads? the pump that i have in the sump right now is a rio2100 i think, something like 650gph minus head loss which is 5 feet now, and will increase to 6 feet when on the new stand
 
well its up to you. lay it flat on the ground the water helps cool the bit and the glass. if you break it get a new peice of glass cut from a glass shop and have them drill it for you. i would get 1in bulckheads. but if it were me i would say if its not broken dont fix it. i would use what is working for now until i could afford a new tank if it broke
 
yea, the water cools, lubricates, and helps carry off the cuttings(glass dust)

oh, and i guess the other question would be where to drill, the tank is 48 inches long, and 24 inches tall, and the water is about an inch down from the top.

so 1 inch, and do what, 1 on each end of the back? ok, then where do i put the returns?
 
yea, thats what i've got now, i was just thinking about getting everything off the rim of the tank, but i guess i'll just stick to the overflow system i have now, at least that way i'm not taking any unnecessary risks with the tank itself....

I am seriously thinking about getting a second overflow box tho... they would work side by side, and would both go to the same spot in the sump, but at least that way if one ever did loose suction, the other would try and keep the tank from overflowing, cause as it is now with the little sump, if i were to loose my syphon, nothing overflows, the pump will go dry before it goes above the rim of the tank. but the new sump will hold 3 times as much water...
and i'm thinking that i could also have a second return pump, and that would allow me to controll the flow in the tank better, and would increase the flow as well...

if you add up the sump, the canister filter, and the powerhead, i'm guessing i have sometihng in the neighborhood of 500-600 gallons per hour in my 75gal tank... is that about right? should i have more? less?

i also have all flow generating devices working in the same direction, making the tank spin in a clockwise direction if viewed from above... is that ok, or is there a better way of setting it up?
 
Sounds like your in good shape with the overflow. I used a HOB overflow for well over 15 yrs and it never failed once. I always felt safe using 1.

500-600 gph is a good rate thru your sump. Typically you want between 5-10 times your tank volume thru the sump. If that's your total flow rate, it's real low for a 75g tank. What kind of powerheads are you using? You can easily get away with using 2 K-4's at 1200gph each.

Change the direction of the flow. You don't want a circular motion...you want a random, chaotic flow. Place the powerheads on opposite sides of the tank and point them at each other.
 
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yea, i was just thinking since i have to tear down the tank anyway, if i was ever gonna drill it, now(well when i move it) would be the time....

I was looking at the korilla powerheads last night when i was at the aquadome...

as of right now all the flow i have is the one rio2100 the canister and one small powerhead, no idea what it flows... it was cheap tho, like 20 bucks at the local mom and pop pet store.

sounds like i need a bunch more flow then...

the other thing that i was looking at while i was hanging out at the lfs last night was a "wave maker" or powerhead controller that could cycle the power back and forth between 2 units, but they wanted like 70 bucks for it, and i was like no way jose, i can build my own for under 20 bucks.. so i guess thats yet another project to add to the list...
 
Hi, I had the same problem a while ago, I wanted to overflow into my refugium , I ended up getting 4x pieces of glass cut and drilled, and simply siliconed them onto the inside topside of my main tank, and not only did it look smart [the extra height] but works a treat with no leaks. This was over a year ago, and it's still ok. Cost..£16. Regards.
 
so am i understanding that you just added to the top of your tank and the extensions were what were drilled.. now thats an interesting idea... how did you get the measurements accurate enough so that the corners sealed up and didnt leak?
 
i can picture what he did in my head, just imagine glueing verticle sheets of glass to each of the sides of your existing tank, glue them to the inside of the tank, so that they stick up above the tope of the existing tank

. but thats where my corner sealing question comes into play, cause my tank has rounded corners, so i cant just add sheets of glass and get them to meet up at the corners...
 
ok i see now. I personally wouldnt trust my glueing to support it all. but im sure there are ways to do it. I would just go with the second over flow though. It would be the simplest and least likely to give you problems.

Brian
 
Yea, I’m so scared of breaking this one big tank that I have that I think I will just go to a second overflow... I like the idea of having some redundancy... my one fear with a second overflow, is that I will have to increase my pump volume coming up from the sump to the DT, my thinking was to run 2 pumps, again for redundancy, but my fear is that one of the pumps could fail, and thus not keep enough flow moving so as to keep the air bubbles from collecting in the u-bend tubes, and thus causing that old siphon breakage issue that I had when i didn’t have enough pump to cause enough flow to blow them out of the u-bend...
 
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